paf_366_752 Patricia Fox Lawrence Berkeley National Laboratory pmfox@lbl.gov http://orcid.org/0000-0002-5264-1876 Christian Dewey Stanford University cwdewey@stanford.edu http://orcid.org/0000-0003-1954-8298 Cam Anderson University of Massachusetts Amherst cganderson@umass.edu http://orcid.org/0000-0003-4211-5765 Marco Keiluweit University of Massachusetts Amherst keiluweit@umass.edu Peter Nico Lawrence Berkeley National Laboratory psnico@lbl.gov http://orcid.org/0000-0002-4180-9397 U.S. DOE > Office of Science > Biological and Environmental Research (BER) http://dx.doi.org/10.13039/100006206 fundingOrganization 2021 This dataset includes groundwater geochemistry data from floodplain piezometers collected as a part of the Watershed Function Scientific Focus Area (SFA) located in the Upper Colorado River Basin. The data were collected in order to investigate the role of hyporheic exchange and other river corridor processes on riverine export of solutes. Floodplain piezometers installed in Meander Z (MZA, MZB wells) and Meander Y (MYP wells) just upstream of the confluence with Brush Creek were sampled on daily to weekly time scales during summer-fall 2018. Some river water grab samples are also included. Data includes in-field measurements (pH, electrical conductivity [EC], oxidation reduction potential [ORP], and groundwater level) along with laboratory measurements (dissolved inorganic carbon [DIC], dissolved organic carbon [DOC], metals and major cations, anions [chloride, sulfate, nitrate], and dissolved ammonium). Five files are included in this dataset, including: sample locations and depths in both a kmz file which can be opened in Google Earth and a csv file, sampling protocol as a pdf document, aqueous geochemistry data in a csv file, and analytical detection limits in a csv file. anion cation groundwater floodplain river corridor CATEGORICAL:NONE Anions Cations Dissolved Ammonia Patriculate/Dissolved Inorganic Carbon Patriculate/Dissolved Organic Carbon VARIABLE:NONE

Additional metadata on specific locations within the watershed are provided in the following related data package: Varadharajan C ; Kakalia Z ; Banfield J ; Berkelhammer M ; Brodie E ; Christianson D ; Dafflon B ; Carbone M S ; Carroll R ; Chadwick K D ; Christensen J ; Enquist B J ; Fox P ; Henderson M ; Gochis D ; Kueppers L ; Powell T ; Matheus Carnevali P ; Singha K ; Sorensen P ; Tokunaga T ; Versteeg R ; Wilkins M ; Williams K ; Worsham M ; Wu Y ; Agarwal D (2020): Location Identifiers, Metadata, and Map for Field Measurements at the East River Watershed, Colorado, USA. Watershed Function SFA. doi:10.15485/1660962

This work is licensed under the Creative Commons Attribution 4.0 International License. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/. 2018-06-01 2018-10-03 The East River (ER) is a snow‐dominated, headwater basin of the Upper Colorado River Basin (UCRB) located in the western United States. The ER is the designated testbed of Lawrence Berkeley National Laboratory's Watershed Function Scientific Focus Area (WFSFA). Through WFSFA, observational networks have been established to measure stream discharge and precipitation chemistry. The ER is considered representative of many snow‐dominated headwaters of the Rocky Mountains. The study domain encompasses nearly 85 square km, a 1.4‐km vertical drop in elevation (4,120 to 2,760 m) and pristine alpine, subalpine, montane, and riparian ecosystems. The ER contains high‐energy mountain streams to low‐energy meandering floodplains and is eroding primarily into the Cretaceous, carbon‐rich, marine shale of the Mancos Formation. Additional metadata on specific locations within the watershed are provided in the following related data package: Varadharajan C. et al. (2020) doi:10.15485/1660962 -107.05 -106.88 39.034 38.88 Patricia Fox Lawrence Berkeley National Laboratory pmfox@lbl.gov http://orcid.org/0000-0002-5264-1876 Manual water level measurements were performed using an electrical water level meter and are reported in cm bgs (cm below ground surface). Groundwater samples were collected using a peristaltic pump from piezometers. River water samples were collected using a nylon syringe. A multi-parameter probe was used to measure pH, electrical conductivity (EC, mS/m) and oxidation-reduction potential (ORP, mV) immediately after sampling in the field. Dissolved oxygen (DO) and Fe(II) were measured colorimetrically in the field using a portable spectrophotometer (CHEMetrics, Inc.). Filtered samples (0.45 um PVDF syringe filter) were collected for anions (Cl, SO4, and NO3), dissolved inorganic carbon (DIC), dissolved organic carbon (DOC), ammonium (NH4), and cations (various elements) and shipped to the lab for analysis. Exact volumes and bottle types for each sample are described in the "East River geochem sampling protocol" file. DO was measured on unfiltered groundwater using either with the indigo carmine method (Chemetrics #K-7513, 1–15 ppm) or the Rhodazine D™ method (Chemetrics #K-7553, 0–1 ppm). Fe(II) was measured on filtered groundwater using the phenanthroline method (Chemetrics #K-6203, 0-6 ppm). Anion samples were refrigerated at 4 degC for storage and shipment, and analyzed by ion chromatography (IC) using a Dionex ICS-2100 IC (Thermo Scientific). DIC and DOC samples were refrigerated at 4 degC for storage and shipment. Groundwater samples were analyzed for total dissolved carbon and dissolved organic carbon (DOC) on a Shimadzu TOC-V analyzer with a nondispersive infrared detector, and dissolved inorganic carbon was determined by the difference. Total dissolved carbon was measured by catalytically aided combustion at 680 °C, and DOC samples were analyzed by nonpurgeable organic carbon, for which samples were acidified with HCl and purged with N2 in order to remove inorganic carbon prior to the analysis. Ammonium (NH4) samples were acidified to pH 2 using 2 M HCl and refrigerated at 4 degC for storage and shipment. Samples were analyzed by flow injection analysis using the colorimetric salicylate method (Lachat Instruments). Elemental concentrations were measured in "cation" samples by inductively coupled plasma mass spectrometry (ICP-MS, Perkin-Elmer Elan DRC II) after acidification and dilution with ultrapure 0.16 M nitric acid and internal standard addition. Detection limits for each parameter are listed in the data file and were either reported by instrument manufacturer [DO and Fe(II)] or calculated as 5 times the standard deviation of a MilliQ water blank (all others). Any data below the detection limit is reported as "BDL". Empty cells indicate that the parameter was not measured for that sample. Standard deviations (sd) reported for parameters reflect analytical error. Susan Hubbard Lawrence Berkeley National Laboratory sshubbard@lbl.gov Principal Investigator DOE:DEAC0205CH11231 (Lawrence Berkeley National Laboratory) detection limits.csv text/csv 2018_Meander Z_Meander Y_water sampling_archive_v2.csv text/csv East River geochem sampling protocol_2018-2019_v2.pdf application/pdf Brush Creek site_MZ_MY_locations_v2.kmz application/vnd.google-earth.kmz MZ_MY locations.csv text/csv